Pi-oportkns of Carbon in Minimi Coal. ,«- 



Its hardncfs 6. Specific gravity 1,268 by my trials. It burns with a bright flame and 

 quicker than the foregoing, and is lefs apt to cake. 328 grains of it, expofed as the former 

 to aftrong heat, left 5,1 3 grains of athes.that is, 1,57 per cent. 81 grains of it decompofed 

 480 grains of nitre. Hence 100 grains of it contain 61,73 of carbon, 36,7 of a mixture of 

 maltha and afphalt, and 1,57 of a(hes. 



It feems to contain a larger proportion of maltha, with refpea to its quantity of afphalt, 

 than Whitehaven coal does. 



Swanfey Coal. 

 ITS colour is black. 



Its luftre 2. Tranfparency O. 



Its fradure foliated ; but fome lamellae being at right angles with the other, give it a. 

 £brous or llriated appearance. Fragments 2. 



Its hardnefs 5, very brittle. Specific gravity 1,35^7 by my trials. 



It burns more flowly than the former, and cakes. 



240 grains of it, treated as the former kinds, left 8 grains of yellowifli red allies ;. that Ts,, 

 equal 3,33 per cent. 



Of this coal 68 grains were requifite to decompofe 480 grains of nitre. Then 100 

 grains of it contain 73,53 of carbon, 23,14 of a mixture of maltha and afphalt, and 3,32 

 of afhes. The afphalt feems to predominate. 



Ltltrim Coal. 

 ITS colour is black. 



Its luftre when frefh broken 3. Tranfparency o. 



Its fracture foliated. Its fragments 2. 



Its hardnefs 6, very brittle. Specific gravity 1,351 by my trials. It fllghtly cakes. 



240 grains of it left, after three hours expofure to heat, 12,5 grains of reddiih grey 

 aflies, that is, equal 5,2 per cent. 



The decompofition of the ftandard quantity of nitre required 70 grains of this coal. 

 Hence 100 grains of it contain 71,43 of carbon, 23,37 of a mixture of maltha and afphalt' 

 and 5,2 of aflies. 



Ncwcajlle Coal. 

 ^ I HAD none of this kind of coal ; but, according to Dr. Watfon's experiment, it left on 

 diftillatlon a coaly refiduum amounting to 58 per cent, and hence contained about 40 of a 

 mixture of afphalt and maltha, in which the former appears to predominate. Hence it 

 much refembtes the Whitehaven coal •, but it evidently cont.uns fulphur alfo, which that of 

 Whitehaven feldom does. 



wrf fynopt'ual 



